Method and means for increasing the flow of fluid from well casings



Jan. 17, 1939. J, w, VAN METER 2,144,208

METHOD AND MEANS FOR INCREASING THE FLOW OF FLUID FROM WELL CASINGS Filed Aug. 19, 1935 27 25 ze Z4 [Nl/EHTOE: JHME'S WYHNNETEH @www Patented Jan. 17, 1939 UNITED STATES PATENT OFFICE METHOD AND MEANS FOR INCREASING THE FLOW OF FLUID FROM WELL CASINGS Application August 19,

12 Claims.

'I'he present invention relates to a new and novel method and means for perforating well casing in place in a well hole.

'I'he method and apparatus can be used advantageously in existing structures in wells which have become depleted and where, in order to prolong the productive life of the well, it is desirable to open the casing to ingress of fluid from other strata or zones above the depleted one which were drilled through and cemented off originally.

The method and the device can also be used, and with equal advantage, before a new well is put on production. In the latter case a casing can be closed at the bottom, lowered to any desired depth, and be perforated, by my method,

at any desired level or number of levels.

Water veins are often encountered in drilling a well. After the casing has been landed in place and cemented, the casing can be perforated at known oil-producing levels and the water be excluded from the production string.

In the accompanying one sheet of drawings, Figure 1 is a fragmentary view, partly in section, of two concentric well casings, cement interposed. and showing suspended therein a tubular container embodying the chemicals requisite to carry out my method of perforation, and

Figure 2 is a vertical central view, in section, on an enlarged scale, of the tubular container shown in Figure 1.

I am aware that well casing is being perforated by gun-re and by methods wherein projectiles are driven through caslngs and cement surrounding same by explosion of gun-powder and other explosives.

My method differs distinctly from such procedure and is not to be confused therewith.

No projectile is employed in my method and, and instead of relying on explosives to accomplish the work in hand, I employ an intense, localized heat which is generated chemically within the container suspended in the well casing and I direct the discharge against and through the casing after the manner in which an oxyacetylene cutting torch ls operated.

The intense heat generated in said container fuses, or instantly liqueiies, the plug closures of the container and, simultaneously therewith, acts upon oil within the container to create sufficient pressure to drive the molten gaseous product through the orices in which the plugs were seated.

Referring to the drawing the number I indicates, in its entirety, a tubular container adapted to be suspended from a cable 2, and including 1935, Serial No. 36,797

a threaded cap 3 which is provided with a central bore 4, threaded t receive an insulated plug 5.

A filler plug 6 is threaded into cap 3 and provides means for filling a chamber 1 with ingredients to be later described.

An electric conductor 8 extends through the cable 2 and is provided, at its inner end, with a clamp 9, which clamp retains an insulated wire I0, suspended in chamber 1.

A cylindrical barrel section I I, screwed into the threaded cap 3, contains a quantity of oil I2, as indicated in Figure 2.

A wire clamp I3 is secured to the inner or lower end of the Wire Ill, and a sealed metallic cartridge I4 is suspended on said wire in chamber l, and is provided with a closure I5 through which the conductor wire III extends.

Secured to the inner end of this conductor is an ignition cap I6 arranged in a body constituted of a charge of metallic aluminum and ferric oxide mixture.

The lower part of cartridge I4 contains a charge of powdered antimony sulphide I8, and above same is a quantity of metallic aluminum and ferric oxide mixture I'I.

Conductor wire I9 extends through the bodies of chemicals I'I and I8 and is connected to a fusible plug 23 positioned in the lower end of the cartridge.

A base member 2| is internally threaded for engaging and closing the barrel member II and said base embodies a recessed seat in which the cartridge I4 rests.

Said base 2l is centrally bored at 22 to receive a plug 23 of fusible material, such as lead, or other suitable substance. l

Said material is introduced in bore 22 in molten state and the resultant casting embeds the inner threaded end 2l of a tapered plug 24, which may be of steel or any material less malleable than the substance in which its threaded end is embedded.

Plug 24, in turn, is mounted in a correspondinglytapered bushing 25, seated in a tapered bore 26 is the base 2l. A threaded bushing ring 28 holds bushing 25 in locked relation to base 2l.

This structure aiords an effective seal, of sufficient mechanical strength, to resist the tremendous hydrostatic pressures ordinarily encountered in oil wells of great depth.

It is to be clearly understood that the plug 24 is in no sense designed to be a projectile and that its entire function is to effect a seal resistant to external pressure.

Base 2l and cap 3 are provided with wrench seats28 so that members 3, II, and 2I, can be tightly screwed together to provide a hermetically sealed chamber 1 forming a container for the oil I2, in which is suspendedjhe cartridge I4.

I'he cartridge Il is suitably protected from inltration of oil by. .ar covering or envelope of sodium silicate.

In Figure 1 I have illustrated my invention as it would appear when used to perforate an oil well casing 30 within a. large casing 3 I.

A layer of cement is interposed between the two strings of casing.

To facilitate field operation, I employ a suitable mobile element, such as a service truck 32, which is provided with a power-driven cable drum 33, and with a derrick supporting a sheave 34 over which cable 2 passes in raising or lowering the tubular body I.

Said truck carries a battery 35, electrically connected to the connector 8 to supply current thereto to effect ignition of cap I6, when energized.

Operation To perforate a well casing, in place within a well hole, I proceed as follows:

The member I is lowered through casing 30 to the desired depth by unreeling cable 2 from drum 33.

When member I hangs suspended at the desired depth, conductor 8 is energized through the medium of a suitable switch (not shown) and said energization causes ignition cap I6 to create a fusing action between the reactive agents I1 and I8, producing a molten steel mass, which mass instantaneously liquefies the closure I and the fusible plug in opposite ends, respectively, of the cartridge I4.

The excessive heat thus created chemically, raises the temperature of the oil I2 in chamber 1 to 1000 degrees centigrade or more, and simultaneously therewith liquees plugs 23 thereby releasing plug 24 and providing a channel for re- Alease of the gaseous content of chamber I and for directing same against the inner wall of the casing 30. l

Being thus released and directed in concentrated intensity it penetrates the casing 30, disintegrates cement between the casings and 3|, penetrates casing 3| and opens the surrounding formation to increased production through the casing string.

I claim:

1. In a device for perforating a well casing in place in a well hole, the combination of a chemical heat-producing charge, a body holding said charge in suspension in liquid, said body being suiciently strong to resist the force of heat generated by the charge, a lateral opening for directing the force of heat towards the well casing, means normally closing said opening, and means for igniting said charge and fusing a portion of the means normally closing said opening thereby destroying its value as a closure means.

2. The method of perforating a well casing in place in a well hole by melting a hole therein which consists in lowering into the well hole a container having heat-producing chemicals therein, fusing the chemicals by igniting them, and directing the fused chemicals against the casing, thereby melting a hole in it.

' 3. 'I'he method of perforating a well casing in place in a well hole by melting a liole therein which consists in lowering into the well hole a container containing heat-producing chemicals and a fluid therein igniting the chemicals to fuse them, and forcing the fused chemicals against the casing by liberating gas from the fluid heated by the fused chemicals.

4. The method of perforating a wellV casing in place in a well hole by melting a hole therein which consists in lowering into the well hole a container having therein a powdered antimony sulphide and metallic aluminum and ferric oxide mixture in oil fusing the chemicals into a molten mass by igniting them, heating the oil by the heat produced by the chemicals, and forcing the molten mass against the casing by utilizing the pressure of the heated oil.

5. A device for perforating a well casing in place in a well hole which comprises: a container having a chamber therein and a plugged outlet; a quantity of oil in said chamber; a cartridge containing heat-generating chemicals in said chamber adjacent said plugged outlet capable of converting a substantial portion of said oil to gas when ignited; an ignition cap in said cartridge; and electrical means for setting oif said ignition cap. Y

6. A device for perforating a well casing in place in a well hole which comprises: a container having a chamber therein and a plugged outlet; a substance adapted to materially expand at high temperatures in said chamber; a sealed cartridge in said chamber adjacent said outlet containing an antimony sulphide, metallic aluminum and ferrie oxide mixture and an ignition cap; and electrical means for setting olf said ignition cap.

'7. A device for perforating a well casing in place in a well hole which comprises: a container having a chamber therein and an inlet and an outlet for the chamber; a plug in said inlet; a plug in said outlet; a sealed cartridge having an upper and a lower fusible plug and containing a mixture of heat-generating chemicals; a body of oil in said chamber substantially surrounding said cartridge; and electrical means for igniting said chemicals; said chemicals, when ignited, creating temperature sufficient to convert a substantial portion of said oil into gas.

8. A device for perforating a well casing in place in a well hole which comprises: a container having a chamber therein and having an outlet for said chamber; fusible means for closing said outlet; heat-generating chemicals in said chamber adapted to be converted into a molten mass when ignited; a quantity of oil in said chamber; and means for igniting said chemicals.

9. 'I'he method of perforating a well casing in place in a well hole which includes: lowering into said casing a confined mixture of chemical reagents capable of generating intense heat upon ignition; igniting said mixture of reagents; and directing the hot products of reaction in a stream against said well casing to melt an opening therethrough.

10. The method of perforating a well casing in place in a well hole which includes: lowering into said casing a conned mixture of chemical reagents capable of reacting to -form a fluid product of intense heat upon ignition; igniting said mixture of reagents; directing the hot product of reaction in a stream against said well casing to melt an opening therein; and utilizing a portion of the heat of reaction to create a pressure behind said coniined body of reacting mixtures for driving said stream against said casing with substantial force.

11. The method of perforating a well casing in place in a well hole which includes: lowering into said casing a mixture of chemical reagents capable of reacting to form a iiuid product of intense heat upon ignition in a body of material adapted to generate pressure of great magnitude at the reacting temperature of said reagents; igniting said mixture of reagents; directing the hot products of reaction in a stream against said well casing to melt an opening therethrough; and utilizing the pressure created by said pressure generating material to drive said stream of hot fluid against said casing with substantial force.

12. The method of perforating a well casing in place in a well hole which includes: lowering into said casing a charge of powdered antimony sulphide and metallic aluminum and ferric oxide mixture in a body of oil; igniting said charge to generate a. uid product of reaction of intense heat; directing said product of reaction against said casing in a stream to melt an opening therein; and utilizing a portion of the heat generated to vaporize said body of oil for applying pressure.

to said reacting mixture and thereby driving said stream through said casing with substantial '1U force.

JAMES W. VAN METER. 

